Read this excerpt from the count of monte cristo by alexandre dumas:
this time he fell on his knees, and, clasping his hands convulsively, uttered a prayer intelligible to god alone. he soon became calmer and more happy, for only now did he begin to realize his felicity.
what does the word felicity mean in this context?

Although, literally, the word felicity means happiness, but considering the way the word was used in the passage above, the best meaning for the word 'felicity' is GOOD FORTUNE.
The man that is been discussed in the passage was thanking God because, he is just realizing how fortunate he has been. 

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